Eindhoven University of Technology , P.O. Box 513 (STO 3.31), 5600MB Eindhoven, The Netherlands.
Department of Chemistry, Swansea University , Swansea SA2 8PP, United Kingdom.
J Am Chem Soc. 2017 Dec 6;139(48):17309-17312. doi: 10.1021/jacs.7b10846. Epub 2017 Nov 17.
Complex coacervate microdroplets are finding increased utility in synthetic cell applications due to their cytomimetic properties. However, their intrinsic membrane-free nature results in instability that limits their application in protocell research. Herein, we present the development of a new protocell model through the spontaneous interfacial self-assembly of copolymer molecules on biopolymer coacervate microdroplets. This hierarchical protocell model not only incorporates the favorable properties of coacervates (such as spontaneous assembly and macromolecular condensation) but also assimilates the essential features of a semipermeable copolymeric membrane (such as discretization and stabilization). This was accomplished by engineering an asymmetric, biodegradable triblock copolymer molecule comprising hydrophilic, hydrophobic, and polyanionic components capable of direct coacervate membranization via electrostatic surface anchoring and chain self-association. The resulting hierarchical protocell demonstrated striking integrity as a result of membrane formation, successfully stabilizing enzymatic cargo against coalescence and fusion in discrete protocellular populations. The semipermeable nature of the copolymeric membrane enabled the incorporation of a simple enzymatic cascade, demonstrating chemical communication between discrete populations of neighboring protocells. In this way, we pave the way for the development of new synthetic cell constructs.
复杂凝聚体微滴由于其类似细胞质的特性,在合成细胞应用中得到了越来越多的应用。然而,它们内在的无膜性质导致了不稳定性,限制了它们在原细胞研究中的应用。在此,我们通过共聚物分子在生物聚合物凝聚体微滴上的自发界面自组装,提出了一种新的原细胞模型的发展。这种分层原细胞模型不仅结合了凝聚体的有利特性(如自发组装和大分子缩合),还吸收了半透性共聚物膜的基本特征(如离散化和稳定化)。这是通过工程设计一种不对称的、可生物降解的三嵌段共聚物分子来实现的,该分子包含亲水性、疏水性和聚阴离子成分,能够通过静电表面锚固和链自组装直接进行凝聚体膜化。所得到的分层原细胞由于形成了膜而表现出显著的完整性,成功地稳定了酶货物,防止在离散的原细胞群体中聚集和融合。共聚物膜的半透性质允许简单的酶级联的掺入,证明了相邻原细胞群体之间的化学通讯。通过这种方式,我们为新型合成细胞构建的发展铺平了道路。